The grey areas are the places that contain DNA, and the different colors are the mixtures of the different fruits, the Dawn detergent, the meat tenderizer, the salt, and the ethyl alcohol. As is seen, the DNA in the banana test tube showed to be most prominent, followed by the DNA in the kiwi, and then the DNA in the strawberry.
Conclusion:
The results of the lab followed the general procedure that the soap will help dissolve the phospholipid bilayers of the cell membranes and organelles. The salt is used to break up protein chains that bind to the around the nucleic acids. The alcohol is used to precipitate the DNA so that it is easily visible. The results show that the banana contains the most DNA, followed by the kiwi, and lastly the strawberry. This, however, does not concur with existing ideas that the strawberry should have the most DNA. Since a strawberry has a large genome, being an octoploid, it was expected that the most DNA would be extracted from it. Bananas have triploid sets of chromosomes and kiwi has diploid sets of chromosomes, both of these being less than that of strawberries. This could signify that the strawberry was expected to have more DNA extracted than both of the other fruits. According to some researchers, this data could fit possibly make sense. It is not only the number of chromosomes that determines the amount of DNA in a cell but the length and thickness of the chromosomes. Since there is research that shows that there are several species of amphibians and plants that have more DNA per cell than human cells, then there is not entirely accurate to base the amount of DNA that will be extracted from a fruit on the amount of chromosomes the fruit contains.
In order to improve the reliability of my data, I could take measures to make sure that the data is both quantitative and qualitative. I could take this step in using a ruler to measure the exacted amount of DNA in the test tube. I could also do this by scooping the DNA out the test tubes and placing them into graduated cylinders to evaluate the mL amount of DNA. I would probably use a different alcohol and see what kind of effect it has on the DNA of the different fruits, or maybe even try it without using salt or a meat tenderizer.
To learn more about this question, I could compare data with the other people in my class to see if they got the same results. I could also go online and see what kinds of the same lab that I did created the same or different results. To further my investigation of the DNA in these fruits, I could find different methods of extracting the DNA, instead of just using soap and salt. This could potentially give me more accurate data that I could compare to the data achieved by this lab. If I repeated this investigation, I would put the mixture of soap and alcohol into a beaker, and use larger amounts, so it would be easier to see the DNA. This way, I will have a greater amount of data, which could possibly reveal a difference that this lab did not.
Bibliography:
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scienceNOW, NOVA and NOVA. "NOVA and NOVA scienceNOW." 2005. pbs.org. 10 November 2008 <http://www.pbs.org/wgbh/nova/teachers/activities/pdf/3214_01_nsn_01.pdf>.
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Silvert, D. "DNA Extraction from Fruit ." 11 April 2005. Ask A Scientist. 10 November 2008 <http://www.newton.dep.anl.gov/askasci/mole00/mole00596.htm>.
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Swezey, Robert. "Fruitful DNA Extraction." 2000. Exploratorium. 10 November 2008 <http://www.exploratorium.edu/ti/human_body/dna.html>.
